如果存在子类，则将类添加到父类

class Animal:
    def __init__(self, name):
        self.name = name

    def speak(self):
        raise NotImplementedError("Subclass must implement abstract method")

class Dog(Animal):
    def speak(self):
        return f"{self.name} says Woof!"

class Cat(Animal):
    def speak(self):
        return f"{self.name} says Meow!"

# 使用继承的类
dog = Dog("Buddy")
print(dog.speak())  # 输出: Buddy says Woof!

cat = Cat("Kitty")
print(cat.speak())  # 输出: Kitty says Meow!

class Parent:
    def __init__(self, value):
        self.value = value

class Child(Parent):
    def __init__(self, value, extra):
        super().__init__(value)  # 正确调用父类构造函数
        self.extra = extra

class Parent:
    def common_method(self):
        print("This is a common method.")

class Child(Parent):
    def common_method(self):
        super().common_method()  # 调用父类的方法
        print("Additional functionality in child class.")